The aad-1 gene (originally from Sphingobium herbicidovorans) encodes the aryloxyalkanoate dioxygenase (AAD-1) protein. The trait confers tolerance to 2,4-dichlorophenoxyacetic acid and aryloxyphenoxypropionate (commonly referred to as “fop” herbicides such as quizalofop) herbicides and may be used as a selectable marker during plant transformation and in breeding nurseries. The aad-1 gene, itself, for herbicide tolerance in plants was first disclosed in WO 2005/107437 (see also US 2009-0093366).
The expression of heterologous or foreign genes in plants is influenced by where the foreign gene is inserted in the chromosome. This could be due to chromatin structure (e.g., heterochromatin) or the proximity of transcriptional regulation elements (e.g., enhancers) close to the integration site (Weising et al., Ann. Rev. Genet. 22:421-477, 1988), for example. The same gene in the same type of transgenic plant (or other organism) can exhibit a wide variation in expression level amongst different events. There may also be differences in spatial or temporal patterns of expression. For example, differences in the relative expression of a transgene in various plant tissues may not correspond to the patterns expected from transcriptional regulatory elements present in the introduced gene construct.
Thus, large numbers of events are often created and screened in order to identify an event that expresses an introduced gene of interest to a satisfactory level for a given purpose. For commercial purposes, it is common to produce hundreds to thousands of different events and to screen those events for a single event that has desired transgene expression levels and patterns. An event that has desired levels and/or patterns of transgene expression is useful for introgressing the transgene into other genetic backgrounds by sexual outcrossing using conventional breeding methods. Progeny of such crosses maintain the transgene expression characteristics of the original transformant. This strategy is used to ensure reliable gene expression in a number of varieties that are well adapted to local growing conditions.
U.S. Patent Apps. 20020120964 A1 and 20040009504 A1 relate to cotton event PV-GHGT07(1445) and compositions and methods for the detection thereof. WO 02/100163 relates to cotton event MONI5985 and compositions and methods for the detection thereof. WO 2004/011601 relates to corn event MON863 plants and compositions and methods for the detection thereof. WO 2004/072235 relates to cotton event MON 88913 and compositions and methods for the detection thereof.
WO 2006/098952 relates to corn event 3272. WO 2007/142840 relates to corn event MIR162.
U.S. Pat. No. 7,179,965 relates to cotton having a cry1F event and a cry1Ac event.
AAD-1 corn having the specific event disclosed herein has not previously been disclosed.